In the automotive industry, there are numerous methods for securing batteries in position on a vehicle. In the construction industry, the electrical requirements to start the engine and maintain the operation of a vehicle often requires the use of two batteries used in tandem. Since construction vehicles are intended to be operated in extremely rough terrain from time to time, the hardware needed to secure the batteries in place is required to be of heavy duty capacity.
A typical mounting for a pair of batteries includes a metal frame member that rests on top of the batteries as they rest in place on a base plate. The frame typically surrounds the outer extremities of the battery and is secured to the base plate by numerous threaded fasteners that extend between the frame and the base plate. Usually at least two fasteners are spaced from each other at each end of the assembly to provide a clamping force against the batteries to hold them in place.
A design such as this is disclosed in the U.S. Pat. No. 4,129,194 issued on Dec. 12, 1978 to Howard A. Hammond et al. The disadvantages that exist in this and similar designs reside in the relative stiffness of the metal framework. Normally weight is an important factor in the design of the framework, as is accessibility to the batteries for service. If the framework is lightweight and therefore absent a significant amount of cross-bracing, it is often too flexible. Being flexible will allow the frame to deform under the torque of the mounting bolts. This can lead to overtightening of one or more of the mounting bolts which results in "point" loading on the battery case. This often causes the battery casing to crack during vehicle operation. This loading can be reduced by increasing the number of bolts used in the mounting apparatus, however the complexity and time required to assemble and disassemble the apparatus is greatly increased. Cross-bracing may be added to the structure for stiffness and to limit the flexibility of the frame, however this increases the weight and tends to limit the accessibility to the batteries.
An additional drawback is the presence of metal in and around the battery. Due to the corrosive nature of the sulfuric acid in the batteries, the corrosion of metal components is accelerated and has an extremely deleterious effect on the strength and function of the mounting components. Metal also is a good conductor of electricity and, when in contact with the battery, causes a "trickle" discharge of the battery and eventually results in battery failure. Often times the metal framework is dipped in plastic to alleviate these problems. While this does help to prevent corrosion and the discharge of the battery, the plastic material tends to "flow" under the clamping force initially provided by the fasteners. As times goes on and the apparatus is subject to shock and vibration, the mounting hardware can become loosened and the batteries will work free.
Another type of mounting for a battery is disclosed in U.S. Pat. No. 3,894,607, issued on July 15, 1975 to James E. Brock. This patent discloses a pair of batteries that are held in place by a single fastening means. The fastening means includes a nut that engages a threaded rod that extends upwardly between the two batteries. A pair of bearing members extend between the nut and the inner edges of the batteries to transmit and spread the torque of the nut along a substantial length of the batteries. While this mounting structure is simple in design, it must be noted that the battery terminals and associated cable clamps are left exposed to the environment. This can be a problem especially in an engine compartment wherein the use of various tools are required for repair and maintenance. Since the pair of batteries are mounted in side-by-side relation to each other, they form a natural shelf. It is very common for service personnel to place tools on top of the batteries for storage while working. With the battery terminals being exposed as they are, it is very possible for one or more tools to come into contact with two of the battery terminals and cause a discharge of electricity between them. In addition to causing damage to the batteries, it may create a dangerous situation for the serviceman.
The present invention is directed to overcoming one or more of the problems as set forth above.